A variety of medical conditions have been treated by introducing an insertable medical device having a coating for release of a therapeutic agent. For example, various types of medical devices coated with a therapeutic agent, such as stents, have been proposed for localized delivery of such agents to a body lumen. See, e.g., U.S. Pat. No. 6,099,562 to Ding et al. issued on Aug. 8, 2000. However, it has been noted that therapeutic agent delivery by means of medical devices can be improved.
In particular, the effectiveness of coated medical devices is limited by the surface area of the medical device. This problem is exacerbated when the medical device is used to delivery biopharmaceuticals, such as gene therapies and proteins. Generally, biopharmaceuticals have large therapeutic application windows. The use of coated medical devices makes the upper areas of these windows difficult or impossible to explore and test because of the limited carrying capacity of a coated medical device. The present invention provides a medical device that has increased carrying capacity to address this and other needs.
It is therefore an objective of the present invention to allow for increased therapeutic agent elution capabilities while still preserving the benefits of expandable medical devices.